Q&A - PSLE Math

[tianzhu]

peggy:

Please help with this CA1 from Ai Tong.


In a survey, some pupils were asked if they preferred volleyball or table tennis. 13/20 of the pupils chose volleyball, 75% of the pupils chose table tennis and 5% of the pupils did not choose any of the two sports. Given that 90 pupils chose both volleyball and table tennis, how many pupils took part in the survey ?

thank you !

Hi

13/20 ------ 65% ------- volleyball
75% ------- table tennis

100% - 5% ------- 95% -------- pupils who chose any of the two sports.

140% - 95% ------ 45% -------- pupils who chose both volleyball and table tennis

45% ------ 90

100% ------- 200

Best wishes

[superksmum]

Pls help with this question:


A lion and zebra were 138m apart. Upon seeing the lion, the zebra ran away from the lion at average speed of 16m/s. The lion observed the zebra for 1 minute before giving chase at an average speed of 25m/s. From the time it started giving chase, how long did the lion take to catch up with the zebra?

Thank you.

[peggy]

tianzhu:

peggy:

Please help with this CA1 from Ai Tong.


In a survey, some pupils were asked if they preferred volleyball or table tennis. 13/20 of the pupils chose volleyball, 75% of the pupils chose table tennis and 5% of the pupils did not choose any of the two sports. Given that 90 pupils chose both volleyball and table tennis, how many pupils took part in the survey ?

thank you !

Hi

13/20 ------ 65% ------- volleyball
75% ------- table tennis

100% - 5% ------- 95% -------- pupils who chose any of the two sports.

140% - 95% ------ 45% -------- pupils who chose both volleyball and table tennis

45% ------ 90

100% ------- 200

Best wishes

Thanks, Tianzhu.

But any possibility of a mode. Think my DS can digest better with it.

Sorry to trouble you.

[tianzhu]

peggy:

Thanks, Tianzhu.

But any possibility of a mode. Think my DS can digest better with it.

Sorry to trouble you.

Hi

Hope this helps.

Best wishes.

http://farm8.staticflickr.com/7243/6966119100_e47f2d8176_z.jpg\">

[tianzhu]

superksmum:

Pls help with this question:


A lion and zebra were 138m apart. Upon seeing the lion, the zebra ran away from the lion at average speed of 16m/s. The lion observed the zebra for 1 minute before giving chase at an average speed of 25m/s. From the time it started giving chase, how long did the lion take to catch up with the zebra?

Thank you.

Hi

As in any questions on Speed, start with a simple diagram.

In 1 min (60 seconds) , the zebra covered (16*60) or 960m.

138 + 960 ----- 1098

25 – 16 ----- 9

1098/9 ------ 122

Time for lion to catch up with zebra ------- 122 seconds.

Best wishes

[superksmum]

Hi Tianzhu,


Thank you so much for the explanation. My DD is able to understand the concept.
Just wonder how to insert a picture or diagram as there is also another question on circle that we are very confused.

Thank you

[tianzhu]

superksmum:

Hi Tianzhu,


Thank you so much for the explanation. My DD is able to understand the concept.
Just wonder how to insert a picture or diagram as there is also another question on circle that we are very confused.

Thank you

Hi

You’re welcome.

You may insert image by following these steps.

1) Do a print screen of the portion you want to upload.

2) Edit using Paint. Cut out the portion of the question you want to upload.

3) Save file in pictures

4) Go to Flickr (Free sign up as member) or other storage sites. Upload file. Select biggest/medium size. Right click to copy URL of image.

5) Coming back to Kiasuparents forum, click insert image button.

Alternatively, if the question is from past years papers, you may just provide a link to the test paper (name of school, year). Please indicate the question number and page number of the paper.

http://www.orlesson.org/orp/MathExam.html

Best wishes

[superksmum]

Sure, will to figure out. However, the question is not from any past year test papers. Hence, will need to try out before posting. It is a worksheet given by school teacher.

Thank you.

[buggy]

Hi all,


Need help in the following questions for my child. Thanks in advance for any help

Q1) Abel had 42 stickers more than Sherrie at first. Abel use 1/6 of his stickers, while Sherrie used 1/4 of her stickers. After that Abel had 45 more stickers than Sherrie. How many stickers did Abel have at first?

Q2) Gina had a box of RED, BLUE and GREEN counters. The ratio of RED counters to BLUE counters was 5:2. The ratio of BLUE counters to GREEN counters was 3:5.
(a) What was the ratio of RED counters to BLUE counters to GREEN counters? - my kiddo seems to know how to do this
(b) After Gina took out 126 RED counters from the box, 1/3 of the remaining counters were RED. How many counters were left in the box?

Q3) The ratio of the number of beads Kenny has to the number of beads Sarah is 7:5. When Sarah gives 48 beads to Kenny, she has 1/3 of the number of beads Kenny has.
(a) How many beads does Kenny have after receiving the beads from Sarah?
(b) How many beads must Kenny give back to Sarah so that she will have 5 times as many beads as him?

[MathIzzzFun]

buggy:

Hi all,


Need help in the following questions for my child. Thanks in advance for any help

Q1) Abel had 42 stickers more than Sherrie at first. Abel use 1/6 of his stickers, while Sherrie used 1/4 of her stickers. After that Abel had 45 more stickers than Sherrie. How many stickers did Abel have at first?

Q1.
At first,
Abel --> 12u + 42, so 1/6 --> 2u + 7
Sherrie --> 12u, so 1/4 --> 3u

In the end,
Abel --> 10u + 35
Sherrie --> 9u
Abel had 45 more stickers than Sherrie,
10u + 35 = 9u + 45
1u --> 10
At first, Abel's stickers --> 12 x 10 + 42 = 162

cheers.